Reduction of Nitro Group by Sulfide and Its Applications in Amine Synthesis

Aniline and its derivatives, as the basic aromatic amine compounds, are widely used in different fields such as chemistry, biology, medicine, dyes, polymer materials and agriculture.Moreover, hydrogenation reduction of nitrobenzene is a simple method for the synthesis of aniline.According to the difference of proton/electron donor, the reduction of nitrobenzene can be divided into Bechamp reduction, catalytic hydrogenation, catalytic hydrogen transfer and Zinin reduction.Zinin reduction is a method for preparing aniline by reducing nitro group by using sulfide as electron donor and protic solvent as hydrogen source, which is widely used in the laboratory research and industrial production.In this review, Zinin reduction method is systematically summarized.The principle of reduction of nitro group by sulfide is clarified from the types of sulfide reductants, the reduction mechanism of nitro group, and the application of nitro group reduction.Additionally, the reduction mechanism of nitro group by elemental sulfur, sulfide, polysulfide and hydrosulfide is detailly elucidated, and the regulatory mechanism of OH -and H2O in the reduction of nitro group by sulfide is explained in detail.Finally, the ability and application effect of different sulfides as reductants to reduce nitro group are analyzed in terms of atom economy.